1. Field of the Invention
The present invention relates generally to the field of band saws and more specifically, those saws used to sever runners or stringers from deck boards of a pallet or skid.
2. Description of the Prior Art
Wooden pallets or skids become damaged through continued use and particularly as a result of contact with the forks of forklift trucks. Wooden pallets have a plurality of parallel top deck boards and bottom deck boards spaced apart but secured together by wooden runners that extend crosswise relative to the deck boards. The deck boards and runners are secured together by conventional fastening devices, such as by nails. Typical pallet damage occurs when the runner located at the end of the pallet is split or otherwise damaged by the lifting device. A solution is to insert a new runner between the deck boards while fastening the new runner inwardly of and to the damaged runner. The pallet is therefore structurally sound; however, the amount of space between the added end runner and the runner which extends at the midway point across the pallet or to the runner located at the opposite end of the pallet is reduced. Certain robotic machines have lifting arms spaced apart to fit exactly into the pallet between the original undamaged runners. As a result of the aforementioned repair technique of inserting an additional runner, the amount of space between runners is reduced and thus such a pallet does not allow certain robotic lifting arms to be inserted therein. Pallets are therefore classified according to whether or not a pallet has been damaged or repaired as described. For example, the value of a pallet that is not damaged typically may be $5.00 to $5.50 each whereas a pallet that has been damaged but repaired by the addition of an additional interior runner has a worth of only approximately $1.50 to $2.50 each. The aforementioned repair technique therefore has serious financial consequences.
It is therefore desirable to completely remove the damaged runner from the pallet in a cost effective manner. One technique is to utilize the band saw disclosed in our U.S. Pat. No. 6,128,992 wherein a pair of band saws simultaneously sever the fasteners securing the opposite deck boards to the runners. In lieu of utilizing a pair of band saws along with the associated drive mechanisms, it is desirable to provide a device having a single band saw wherein the saw may be used to sever the fasteners securing the bottom and top deck boards to the runner. Disclosed herein is such a saw supported for movement above a table allowing the pallet to be pivoted by a single operator enabling the same saw to be used for severing the bottom deck board fasteners as well as the top deck board fasteners.
U.S. Pat. No. 5,323,525 issued to John L. Johnson discloses a cutter head for a pallet dismantling machine. In many cases, round disc type pallet dismantlers cause damage to the deck boards and leave nail stubble. Additional techniques, include a common band saw used to saw into the pallet between the end runners and deck boards with the pallet then being pulled backwards, the pallet flipped over and the opposite deck boards then being sawed from the runners. A problem develops when the pallet is pulled backwards to extricate the saw blade from within the pallet since the saw blade teeth are on the trailing edge of the saw as the saw is moved from the pallet.